Question

type your answer in exactly as one of the following: population, sample, srs, systematic, stratified, cluster, multistage, voluntary, convenience, survey, observation, experiment, undercoverage, response, nonresponse (answer the multiple choice with a uppercase letter) 1) the teacher asks her students to write down all they eat in a day and then calculate the number of calories consumed. is this an experiment or observational study? 2) many websites like amazon and yelp include customer ratings and reviews of products, restaurants, hotels, and so on. what is the predominant bias evident in these ratings and reviews?

Explanation:

1) Step1: Identify study type

The teacher observes students' existing eating habits without manipulating variables. So it's an observational study.

2) Step1: Identify bias type

Reviews are submitted by users who choose to participate, which is voluntary bias.

Answer:

1. OBSERVATIONAL STUDY
2. VOLUNTARY